title: Dose-volume thresholds and smoking status for the risk of treatment-related pneumonitis in inoperable non-small cell lung cancer treated with definitive radiotherapy.
abstract: OBJECTIVE
  To identify clinical risk factors and dose-volume thresholds for treatment-related pneumonitis (TRP) in patients with non-small cell lung cancer (NSCLC).
  
  
  METHODS
  Data were retrospectively collected from patients with inoperable NSCLC treated with radiotherapy with or without chemotherapy. TRP was graded according to Common Terminology Criteria for Adverse Events, version 3.0, with time to grade > or = 3 TRP calculated from start of radiotherapy. Clinical factors and dose-volume parameters were analyzed for their association with risk of TRP.
  
  
  RESULTS
  Data from 576 patients (75% with stage III NSCLC) were included in this study. The Kaplan-Meier estimate of the incidence of grade > or = 3 TRP at 12 months was 22%. An analysis of dose-volume parameters identified a threshold dose-volume histogram (DVH) curve defined by V(20) < or = 25%, V(25) < or = 20%, V(35) < or = 15%, and V(50) < or = 10%. Patients with lung DVHs satisfying these constraints had only 2% incidence of grade > or = 3 TRP. Smoking status was the only clinical factor that affected the risk of TRP independent of dosimetric factors.
  
  
  CONCLUSIONS
  The risk of TRP varied significantly, depending on radiation dose-volume parameters and patient smoking status. Further studies are needed to identify biological basis of smoking effect and methods to reduce the incidence of TRP.
authors.affiliation: Department of Radiation Oncology, Hunan Tumor Hospital and Institution, Hunan, China.
authors.forename: Hekun
authors.initials: H
authors.lastname: Jin
authors.forename: Susan L
authors.initials: SL
authors.lastname: Tucker
authors.forename: Hui Helen
authors.initials: HH
authors.lastname: Liu
authors.forename: Xiong
authors.initials: X
authors.lastname: Wei
authors.forename: Sue Sun
authors.initials: SS
authors.lastname: Yom
authors.forename: Shulian
authors.initials: S
authors.lastname: Wang
authors.forename: Ritsuko
authors.initials: R
authors.lastname: Komaki
authors.forename: Yuhchyau
authors.initials: Y
authors.lastname: Chen
authors.forename: Mary K
authors.initials: MK
authors.lastname: Martel
authors.forename: Radhe
authors.initials: R
authors.lastname: Mohan
authors.forename: James D
authors.initials: JD
authors.lastname: Cox
authors.forename: Zhongxing
authors.initials: Z
authors.lastname: Liao
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D015897:Comorbidity; D004307:Dose-Response Relationship, Radiation; D005260:Female; D006801:Humans; D015994:Incidence; D008175:Lung Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D017564:Radiation Pneumonitis / Q000453:epidemiology / Q000209:etiology*; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents